Potassium compounds for gamma spectrometer efficiency verification

Now-a-days several standard and well calibrated radioactive sources are available for gamma spectrometer efficiency calibration but at some situations, like lack of standard calibrators, in need of verification of standards or preparation a standard with the same properties with the interested sample, 40K is a cheap and easily available radioisotope that could be used. In this study, eighteen different inorganic potassium compounds that have different potassium abundances, types of elements, densities and particle sizes were studied as efficiency verification sources. Gamma spectrometric measurements were performed and it was dawn on the compounds which have low density, low molecular weight and high potassium abundance showed higher 40K activity concentration. It was also indicated that potassium abundance of the compound was the dominant property in these parameters. The activity concentrations were also calculated theoretically and results were in good agreement with the experimental results. Thus it was reported that the 40K compounds with these properties are much suitable for to use as verifying sources or gamma calibrators.